1. Field of the Invention
The present invention relates to data storage devices for apparatuses such as computers, and more particularly to a data storage device incorporating a series of dampers for absorbing vibration and improving dynamic properties of the data storage device.
2. Description of Related Art
Various data storage devices are installed in electronic apparatus for communication and handling of data. Such devices include, for example, hard disk drives, floppy disk drives and CD-ROM (Compact Disk-Read Only Memory) drives. Such data storage devices are being required to meet increasingly stringent physical and operating environment requirements. In particular, durability under harsh environmental conditions is an essential characteristic of a data storage device installed in a modern portable computer.
In current disk drive products, the most commonly used type of actuator is a rotary moving coil actuator. Disks themselves are typically mounted on a hub. Disk flanges or disk spacers are used to mount the disks. Every disk has a circular inner hole stamped therein to receive the hub. Any residual distortion of an inside periphery of the disk resulting from the stamping process can adversely affect the surface condition of the entire disk, because the affected surface is forced down against another component like a disk flange or a disk spacer or clamp.
Digital data are written to and read from a thin layer of magnetized material on the surface of rotating disks. Writing and reading operations are performed by a transducer, which is carried in a slider body. The slider and transducer are sometimes collectively referred to as a head, and typically a single head is associated with a single disk surface. The heads are selectively moved under the control of electronic circuitry to any circular, concentric data tracks on the disk surface by an actuator device. As the disk rotates, the air above the surface of the disk develops a self-acting lifting force that causes the head to lift and fly several microinches above the disk surface. As the flying height of the head above the disk sometimes comes down, there is a need to minimize the inherent vibration of components that make up the disk stack so that the heads can be safely flown across the disk surface while the flying height is reduced. In particular, it is necessary to minimize the impact on a hard disk arising from the components that make up the disk stack, in order to improve the dynamic head loading properties of the data storage device.
There is also a need to reduce the vibrations caused by external impact or innate instability of the disk stack or head stack, in order to minimize the risk of damage to the hard disk surfaces.
However, in a typical data storage device, a spindle motor is directly attached to a baseplate by screws, which constitutes a so-called hard connection. With a typical data storage device having a hard connection, it is problematic to keep the data storage device under stringent physical and operating environments so that it can operate normally.